Friction-assisted tube fabrication method

ABSTRACT

A friction assisted tube fabrication method is disclosed. The friction assisted tube fabrication includes a set of methods such as a friction assisted tube forming, a friction assisted tube extrusion, and a friction assisted tube straining method. A metal object, for example, a deformable tube is simply deformed into the tube using a mandrel. The metal object with an initial diameter is forced across the slope of the mandrel with an angle. The mandrel is configured to rotate while forcing the metal object to deform into the tube with the desired radius. While rotating the mandrel, a friction is generated due to contact between the tube and the mandrel, thereby generating thermal energy to heat a deformation area of the tube for simply and easily softening and forming into the desired shape with accuracy diameter, and dimensions using a nominal pressing force without additional equipment and power.

BACKGROUND OF THE INVENTION

Metal forming is a metalworking process of fashioning metal parts and objects through mechanical deformation. A workpiece or a material is reshaped without adding or removing material. Forming operates on the materials science principle of plastic deformation, where the physical shape of a material is permanently deformed. Currently, applications of high strength material in various industries have been expanding. Although many strengthening methods have been developed in the last years, all of them have limitations to process metal objects, for example, elongated members and tube products because it requires more equipment and high processing force and power. Therefore, conventional processes and methods cannot be applied in an industrial scale.

In addition, the formed metal objects should have mechanical properties and desirable dimensions such as an inner diameter, an outer diameter, and a thickness with high accuracy. When the accuracy of the dimensions is inferior and more largely deviated and as a result, the fatigue strength of the metal object, for example, a pipe or a tube, is extremely decreased. For maintaining a sufficient fatigue strength, the accuracy of the dimensions such as thickness, an inner diameter, and an outer diameter of the metal object, for example, a pipe or a tube is must be improved. In addition, the smoothness of an interior surface and an exterior surface of the metal object, for example, a pipe or a tube is not satisfactory, and as a result, irregularities are liable to remain thereon.

However, the conventional metal forming methods requires high power and multiple equipment thus increases the cost for forming metal objects. In addition, there is no forming and straining process for tubular products, which could be applied in an industrial scale. In other words, the conventional methods and processes for strengthening tubular products are limited to short lengths and they could not be used in the tube forming industry.

The conventional methods are limited to control the mechanical properties of the metallic materials, for example, tubular products and it is a challenging issue for the conventional processes. In addition, the conventional methods and processes require much power and forces for producing high strength metal objects, for example, tubes or pipes. The conventional methods are suitable for fabricating short length tubes and cannot be applied in industrial scales. Further, the accuracy of the dimensions is inferior and deviates and as a result, the fatigue strength of the metal object, for example, a pipe or a tube, is extremely decreased.

Therefore, there is a clear and present need for a method and apparatus for manufacturing elongated members and metal objects, for example, tubular products with high dimensional accuracy and efficiency in an inexpensive manner. Further, there is also a need for a method and apparatus for friction assisted forming, extrusion, and straining of the metal objects, for example, cylindrical tubes with superior workability and minimum processing force and power.

SUMMARY OF THE INVENTION

The present invention generally relates to a method for fabricating elongated members and tubular products and more particularly relates to a method for friction-assisted forming, extruding, and straining to produce high-strength elongated members and tubular products.

In one embodiment, a friction assisted tube fabrication method includes a set of processes or methods such as a friction assisted tube forming method, a friction assisted tube extrusion/extruding method, and a friction assisted tube straining method. In one embodiment, the friction assisted tube fabrication forms metal objects, such as elongated members or long tubes to a desirable diameter and a thickness with controllable mechanical properties. In one embodiment, a metal object is formed into a tube using the friction assisted tube forming is disclosed. In one embodiment, the metal object could be simply and softly deformed into the tube using the mandrel. In one embodiment, the metal object could be, but not limited to, a deformable tube. In one embodiment, the metal object with an initial diameter or radius is forced across the slope of the mandrel with an angle.

The mandrel is configured to rotate while forcing the metal object to deform into the tube with the desired radius. While rotating the mandrel, a friction is generated due to contact between the tube and the slope of the mandrel, thereby generating thermal energy to heat a deformation area of the tube for simply and easily softening and forming into the desired shape with accuracy radius or diameter and dimensions using a nominal pressing force without additional equipment and power. In one embodiment, the diameter of the deformed tube is simply and softly increased using the mandrel by heating and softening the deformation area using thermal energy generated by friction between the tube and the slope of the mandrel while rotating. During this process, the tube with radius of R₀ passes across the slope of the mandrel with angle of α while rotating, thereby deforming the tube with the desired radius of R₁. In one embodiment, the rotation of the mandrel to feeding the tube, could be in a clockwise direction or a counterclockwise direction or with rotational oscillations.

In one embodiment, a method for friction assisted forming is disclosed. At one step, the metal object, for example, a deformable tube, with an initial diameter or radius is forced across the slope of the mandrel with an angle. Further, at another step, the mandrel is rotated while forcing the metal object to deform into the tube with the desired radius. The tube is in contact with the slope of the mandrel while rotating, thereby generating thermal energy to heat the deformation area of the tube for simply and easily softening and forming into a desired shape with an accuracy diameter or radius and dimensions using a nominal pressing force without additional equipment and power.

In one embodiment, the diameter or radius of the tube could be reduced or decreased to a desired value using the die. In one embodiment, the die is configured to rotatably secure on an external surface of the tube. The die is configured to enable an operator or a user to rapidly rotate over the deformation area of the external surface of the tube. The friction between the die and the deformation area at the external surface of the tube generates thermal energy while rapidly rotating the die over the deformation area of the tube. In one embodiment, the thermal energy could heat the deformation area for simply and easily softening and precisely decreasing the diameter of the tube to a desired value using a nominal pressing force without additional equipment and power.

In one embodiment, the tube is extruded for decreasing thickness using an inner mandrel and a rotatary die is disclosed. In one embodiment, the thickness of the tube could be reduced or decreased to a desired value using the inner mandrel and the die. In one embodiment, the tube is forced across the slope of the inner mandrel. The inner mandrel is configured to securely hold the tube during the friction assisted extruding process. In one embodiment, the die is configured to rotatably secure on an external surface of the tube. The die is further configured to enable an operator or a user to rapidly rotate over the deformation area of the external surface of the tube. The friction between the die and the deformation area at the external surface of the tube generates thermal energy while rapidly rotating the die over the deformation area of the tube. In one embodiment, the thermal energy could heat the deformation area for simply and easily softening and precisely decreasing the thickness of the tube to a desired value using a nominal pressing force without additional equipment and power.

In one embodiment, a method for friction assisted extruding is disclosed. At one step, the tube with an initial thickness is simply forced across the slope of the inner mandrel. Further, at another step, the die is slidably and rotatably secured over the external surface of the tube. The die is rapidly rotated over the deformation area of the tube, thereby generating thermal energy due to contact between the external surface and the die to heat the deformation area of the tube for simply and easily softening and precisely decreasing the tube thickness to a desired value using a nominal pressing force without additional equipment and power.

In one embodiment, a friction assisted tube straining to fabricate a metal object into a tube is disclosed. In one embodiment, the friction assisted tube straining is a straining method in which both states of friction assisted tube forming for increasing and decreasing the diameter or radius of the tube are executed sequentially using the mandrel and the die. In one embodiment, the metal object, for example, a deformable tube is forced across the slope of the mandrel with an angle. In one embodiment, the mandrel is configured to rotate while forcing the metal object to deform into the tube with the desired radius or a diameter. When the tube is pressed to the mandrel, the friction between the mandrel and the tube generates a thermal energy and locally heats the deformation area, while rotating, thereby generating thermal energy to heat the deformation area of the tube for simply and easily softening and forming into the desired shape with accuracy diameter/radius and dimensions using a nominal pressing force without additional equipment and power.

In one embodiment, the die is configured to rotatably secure on an external surface of the tube. The die is configured to enable an operator or a user to rapidly rotate over the deformation area of the external surface of the tube. The friction between the die and the deformation area at the external surface of the tube generates thermal energy while rapidly rotating the die over the deformation area of the tube. In one embodiment, the thermal energy could heat the deformation area for simply and easily softening and precisely decreasing the diameter or radius of the tube to a desired value using a nominal pressing force without additional equipment and power. Therefore, the temperature of the deformation area of the tube is increased and the material flow stress is reduced and could process long elongated members and tubes using the friction assisted straining.

In one embodiment, a method for friction assisted tube straining is disclosed. At one step, the metal object, for example, a deformable tube, with an initial diameter or radius is forced across the slope of the mandrel with an angle. At another step, the mandrel is rotated while forcing the metal object to deform into the tube with the desired radius. The tube is in contact with the slope of the mandrel while rotating, thereby generating thermal energy to heat the deformation area of the tube for simply and easily softening and forming into the desired shape with an accuracy diameter or radius and dimensions using a nominal pressing force without additional equipment and power. Further, at another step, the die is rotatably secured over the external surface of the tube and rapidly rotate the die over the deformation area of the tube, thereby generating thermal energy due to friction between the external surface of the tube and the die to heat the deformation area of the tube for simply and easily softening and precisely decreasing the radius of the tube to a desired value using a nominal pressing force without using additional equipment and power.

One aspect of the present disclosure is directed to a method for friction assisted forming a metal object into a tube, comprising: a) forcing the metal object with an initial radius across the slope of a mandrel with an angle; and b) rotating the mandrel while forcing the metal object to deform into a tube with a desired radius, wherein the tube is in contact with the slope of the mandrel while rotating, thereby generating thermal energy to heat a deformation area of the tube for simply and easily softening and forming into a desired shape with a desired value of radius and dimensions using a nominal pressing force.

In one embodiment the metal object is a deformable tube. In another embodiment, the mandrel is configured to simply increase the radius of the tube by heating and softening the deformation area using thermal energy generated by friction between the tube and the slope of the mandrel while rotating. In one embodiment, the radius of the tube is decreased using a die. In another embodiment, the die is configured to slidably and rotatably secure to an external surface of the tube. In one embodiment, the die is further configured to rotate in a clockwise direction or a counterclockwise direction or with rotational oscillations. In one embodiment, the die is further configured to enable an operator to rapidly rotate over the deformation area of the external surface of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area for simply and easily softening and precisely decreasing the tube radius to a desired value using a nominal pressing force.

Another aspect of the present disclosure is directed to a method for friction assisted extruding a tube, comprising forcing the tube with an initial thickness across the slope of an inner mandrel; and securing a die over an external surface of the tube and rapidly rotating the die over a deformation area of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area of the tube for simply and easily softening and precisely decreasing the tube thickness to a desired value using a nominal pressing force.

In one embodiment, the inner mandrel is configured to securely hold the tube during the friction assist extruding process. In another embodiment, the die is configured to slidably and rotatably secure to an external surface of the tube. In one embodiment, the die is further configured to rotate in a clockwise direction or a counterclockwise direction or with rotational oscillations. In another embodiment, the die is further configured to enable an operator to rapidly rotate over the deformation area of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area of the tube for simply and easily softening and precisely decreasing the tube thickness to a desired value using a nominal pressing force.

Another aspect of the present disclosure is directed to a method for friction assist tube straining to fabricate a metal object into a tube, comprising forcing the metal object with an initial radius across a slope of a mandrel with an angle; rotating the mandrel while forcing the deformable tube to deform the metal object into a tube with a desired radius, wherein the tube is in contact with the slope of the mandrel while rotating, thereby generating thermal energy due to friction between the tube and the slope of the mandrel to heat a deformation area of the tube for simply and easily softening and forming into a desired shape with an accuracy radius and dimensions using a nominal pressing force; and securing a die over an external surface of the tube and rapidly rotating the die over a deformation area of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area of the tube for simply and easily softening and precisely decreasing the radius of the tube to a desired value using a nominal pressing force.

In one embodiment, the metal object is a deformable tube. In another embodiment, the mandrel is configured to simply increase the radius of the tube by heating and softening the deformation area using thermal energy. In one embodiment, the thermal energy is generated due to friction between the mandrel and the external surface of the tube while rotating. In another embodiment, the die is configured to slidably and rotatably secure over the external surface of the tube. In one embodiment, the die is further configured to enable an operator to rapidly rotate over the deformation area of the external surface of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area for simply and easily softening and precisely decreasing the tube radius to a desired value using a nominal pressing force. In another embodiment, the inner mandrel is configured to securely hold the tube. In one embodiment, the die is further configured to enable an operator to rapidly rotate over the deformation area of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area of the tube for simply and easily softening and precisely decreasing the tube thickness to a desired value using a nominal pressing force.

Other objects, features and advantages of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and the specific examples, while indicating specific embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A-1B illustrates a perspective view of a friction assisted tube forming process for increasing of a tube diameter using a mandrel according to an embodiment of the present invention;

FIGS. 2A-2B illustrates a perspective view of a friction assisted tube forming process for decreasing the tube diameter using a die according to an embodiment of the present invention;

FIGS. 3A-3B illustrates a perspective view of a friction assisted tube extrusion for decreasing the tube thickness using the die according to one embodiment of the present invention;

FIGS. 4A-4D illustrates a perspective view of a friction assisted tube straining for increasing and decreasing the tube diameter using the mandrel and the die according to one embodiment of the present invention;

FIGS. 5A-5B shows a perspective view of an empirical setup of the friction assisted tube forming process for increasing the tube diameter according to one embodiment of the present invention;

FIGS. 6A-6B shows a perspective view of an empirical setup of the friction assisted tube forming process for decreasing the tube diameter according to one embodiment of the present invention; and

FIGS. 7A-7B shows a perspective view of an empirical setup of the friction assisted tube extruding process for decreasing the tube thickness according to one embodiment of the present invention.

DETAILED DESCRIPTION

The present invention generally relates to a method for fabricating elongated members and tubular products and more particularly relates to a friction-assisted tube fabrication method used to produce high-strength elongated members and tubular products, wherein the friction-assisted tube fabrication method includes a set of processes or methods such as a friction assisted tube forming method, a friction assisted tube extrusion/extruding method, and a friction assisted tube straining method.

A description of embodiments of the present invention will now be given with reference to the figures. It is expected that the present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Referring to FIG. 1A, a metal object 102 is forming into a tube 106 using a mandrel 104 is disclosed. In one embodiment, a friction assisted tube fabrication includes a set of processes or methods such as a method for friction assisted tube forming, a method for friction assisted tube extrusion/extruding, and a method for friction assisted tube straining. In one embodiment, the friction assisted tube fabrication forms metal objects, such as elongated members or long tubes to a desirable diameter and a thickness with controllable mechanical properties. In one embodiment, the metal object 102 could be simply and softly deformed into the tube 106 using the mandrel 104. In one embodiment, the metal object 102 could be, but not limited to, a deformable tube. In one embodiment, the metal object 102 with an initial diameter is forced across the slope of the mandrel 104 with an angle.

The mandrel 104 is configured to rotate while forcing the metal object 102 to deform into the tube 106 with the desired radius. While rotating the mandrel 104, friction is generated due to contact between the tube 106 and the slope of the mandrel 104, thereby generating thermal energy to heat a deformation area 108 of the tube 106 for simply and easily softening and forming into the desired shape with accuracy radius or diameter and dimensions using a nominal pressing force without additional equipment and power. In one embodiment, the mandrel 104 is further configured to simply increase the diameter or radius of the tube 106.

Referring to FIG. 1B, the mandrel 104 is configured to increase the diameter of the deformed tube 106 is disclosed. In one embodiment, the diameter of the deformed tube 106 is simply and softly increased using the mandrel 104 by heating and softening the deformation area 108 using thermal energy generated by friction between the tube 106 and the slope of the mandrel 104 while rotating. During this process, the tube 106 with radius of R₀ passes across the slope of the mandrel 104 with angle of α while rotating, thereby deforming the tube 106 with the desired radius of R₁. In one embodiment, the rotation of the mandrel to feeding the tube 106, could be in a clockwise direction or a counterclockwise direction or with rotational oscillations.

When the tube 106 is pressed to the mandrel 104, the contact between the mandrel 104 and the tube 106 generates a thermal energy and locally heats the deformation area 108, while rotating, thereby generating thermal energy to heat the deformation area 108 of the tube for simply and easily softening and forming into the desired shape with accuracy diameter/radius and dimensions using a nominal pressing force without additional equipment and power. In one embodiment, the friction assisted sssforming is efficiently and effectively used for fabricating longer tubs with various deformation ratios. The contact between the tube 106 and the mandrel 104 also twists the tube 106 just in the deformation area 108 and increases imposed strains.

In one embodiment, a method for friction assisted forming is disclosed. At one step, the metal object 102, for example, a deformable tube, with an initial diameter or radius is forced across the slope of the mandrel 104 with an angle. Further, at another step, the mandrel 104 is rotated while forcing the metal object 102 to deform into the tube 106 with the desired radius. The tube 106 is in contact with the slope of the mandrel 104 while rotating, thereby generating thermal energy to heat the deformation area 108 of the tube 106 for simply and easily softening and forming into the desired shape with an accuracy diameter or radius and dimensions using a nominal pressing force without additional equipment and power.

Referring to FIGS. 2A-2B, the diameter of the tube 106 is extruded using a die 110 is disclosed. In one embodiment, the diameter or radius of the tube 106 could be reduced or decreased to a desired value using the die 110. In one embodiment, the die 110 is configured to rotatably secure on an external surface of the tube 106. The die 110 is configured to enable an operator or a user to rapidly rotate over the deformation area 108 of the external surface of the tube 106. The friction between the die 110 and the deformation area 108 at the external surface of the tube 106 generates thermal energy while rapidly rotating the die 110 over the deformation area 108 of the tube 106. In one embodiment, the thermal energy could heat the deformation area 108 for simply and easily softening and precisely decreasing the diameter of the tube 106 to a desired value using a nominal pressing force without additional equipment and power. During this process, the die 110 is slidably position with an angle of β over the deformation area 108 of the tube 106 with a radius of R₁ and extruded the deformation area 108 by rapidly rotating the die 110, thereby deforming the tube 106 with the desired radius of R₀.

Referring to FIGS. 3A-3B, the tube 106 is extruded for decreasing thickness using an inner mandrel 112 and a rotatary die 110 is disclosed. In one embodiment, the thickness of the tube 106 could be reduced or decreased to a desired value using the inner mandrel 112 and the die 110. In one embodiment, the tube 106 is forced across the slope of the inner mandrel 112. The inner mandrel 112 is configured to securely hold the tube 106 during the friction assisted extruding process. In one embodiment, the die 110 is configured to rotatably secure on an external surface of the tube 106.

The die 110 is further configured to enable an operator or a user to rapidly rotate over the deformation area 108 of the external surface of the tube 106. The friction between the die 110 and the deformation area 108 at the external surface of the tube 106 generates thermal energy while rapidly rotating the die 110 over the deformation area 108 of the tube 106. In one embodiment, the thermal energy could heat the deformation area 108 for simply and easily softening and precisely decreasing the thickness of the tube 106 to a desired value using a nominal pressing force without additional equipment and power.

During this process, the tube 106 with an initial thickness t₀ and a radius of R₁ forces across the slope of the inner mandrel 112 with an angle of λ, thereby extruding the tube 106 with the desired thickness t₁ and the radius of R₁ by rotating the die 110 against to the deformation area 108 of the tube 106. In one embodiment, the die 110 could be rotated in a direction, but not limited to, a clockwise direction or a counterclockwise direction or with rotational oscillations.

When the die 110 is rotatably position over the deformation area 108 of the tube 106, the contact between the die 110 and the tube 106 generates a thermal energy and locally heats the deformation area 108, while rotating the die 110, thereby generating thermal energy to heat the deformation area 108 of the tube 106 for simply and easily softening and extruding the tube 106 for reducing thickness using a nominal pressing force without additional equipment and power. The tube 106 between the die 110 and the inner mandrel 112 undertakes simple shear stress and pure shear by torsion.

A method for friction assisted extruding is disclosed. At one step, the tube 106 with an initial thickness is simply forced across the slope of the inner mandrel 112. Further, at another step, the die 110 is slidably and rotatably secured over the external surface of the tube 106. The die 110 is rapidly rotated over the deformation area 108 of the tube 106, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area of the tube for simply and easily softening and precisely decreasing the tube thickness to a desired value using a nominal pressing force without additional equipment and power.

Referring to FIGS. 4A-4B, a friction assisted tube straining to fabricate a metal object 102 into a tube 106 is disclosed. In one embodiment, the friction assisted tube straining is a straining method in which both states of friction assisted tube forming for increasing and decreasing the diameter or radius of the tube 106 are executed sequentially using the mandrel 104 and the die 110 (shown in FIG. 4C). In one embodiment, the metal object 102, for example, a deformable tube is forced across the slope of the mandrel 104 with an angle. In one embodiment, the mandrel 104 is configured to rotate while forcing the metal object 102 to deform into the tube 106 with the desired radius or a diameter. In one embodiment, the tube 106 is in contact with the slope of the mandrel 104 while rotating, thereby generating thermal energy to heat a deformation area 108 of the tube 106 for simply and easily softening and forming into the desired shape with accuracy diameter and dimensions using a nominal pressing force without additional equipment and power.

During the friction assisted forming, the tube 106 with a radius of R₀ and the thickness of to passes across the slope of the mandrel 104 with angle of α during rotating, thereby deforming the tube 106 with the desired radius of R₁. In one embodiment, the mandrel 104 could be rotated in a clockwise direction or a counterclockwise direction or with rotational oscillations. When the tube 106 is pressed to the mandrel 104, the friction between the mandrel 104 and the tube 106 generates a thermal energy and locally heats the deformation area 108, while rotating, thereby generating thermal energy to heat the deformation area 108 of the tube for simply and easily softening and forming into the desired shape with accuracy diameter/radius and dimensions using a nominal pressing force without additional equipment and power. In one embodiment, the friction assisted forming is efficiently and effectively used for fabricating longer tubs with various deformation ratios. The contact between the tube 106 and the mandrel 104 also twists the tube 106 just in the deformation area 108 and increases imposed strains.

Referring to FIGS. 4C-4D, the diameter or radius of the tube 106 could be reduced or decreased to a desired value using the die 110 is disclosed. In one embodiment, the die 110 is configured to rotatably secure on an external surface of the tube 106. The die 110 is configured to enable an operator or a user to rapidly rotate over the deformation area 108 of the external surface of the tube 106. The friction between the die 110 and the deformation area 108 at the external surface of the tube 106 generates thermal energy while rapidly rotating the die 110 over the deformation area 108 of the tube 106. In one embodiment, the thermal energy could heat the deformation area 108 for simply and easily softening and precisely decreasing the diameter or radius of the tube 106 to a desired value using a nominal pressing force without additional equipment and power.

Therefore, the temperature of the deformation area 108 of the tube 106 is increased and the material flow stress is reduced and could process long elongated members and tubes using the friction assisted straining. During this process, the die 110 is slidably position with an angle of β over the deformation area 108 of the tube 106 with a radius of R₁, thereby decreasing the radius or diameter of the tube 106 with the desired radius of R₀ by rapidly rotating the die 110. This deformation regime imposes plastic strain to the tubes and improves material mechanical properties. The mechanical properties could be controlled when this procedure is repeated for several times.

A method for friction assisted tube straining is disclosed. At one step, the metal object 102, for example, a deformable tube, with an initial diameter or radius is forced across the slope of the mandrel 104 with an angle. At another step, the mandrel 104 is rotated while forcing the metal object 102 to deform into the tube 106 with the desired radius. The tube 106 is in contact with the slope of the mandrel 104 while rotating, thereby generating thermal energy to heat the deformation area 108 of the tube 106 for simply and easily softening and forming into the desired shape with an accuracy diameter or radius and dimensions using a nominal pressing force without additional equipment and power.

Further, at another step, the die 110 is rotatably secured over the external surface of the tube 106 and rapidly rotate the die 110 over the deformation area 108 of the tube 106, thereby generating thermal energy due to friction between the external surface of the tube 106 and the die 104 to heat the deformation area 108 of the tube 106 for simply and easily softening and precisely decreasing the radius of the tube 106 to a desired value using a nominal pressing force.

Referring to FIGS. 5A-5B, an empirical setup of the friction assisted tube forming for increasing the diameter or radius of the tube 106 using a lathe machine 118 is disclosed. In one embodiment, the metal object 102, for example, a deformable tube, is forced across the mandrel 104. In one embodiment, the mandrel 104 is securely positioned between a spindle/chuck 116 and a tailstock 114 of the lathe machine 118. In one embodiment, the spindle 116 is configured to rotate the mandrel 116 with specified rotational speed. The mandrel 104 is configured to deform the metal object 102, for example, a deformable tube into the tube 106 with an increased diameter or radius. The tube 106 is in contact with the slope of the mandrel 104 while rotating, thereby generating thermal energy to heat the deformation area 108 of the tube 106 for simply and easily softening and forming into the desired shape with an accuracy diameter or radius and dimensions using a nominal pressing force without any additional equipment and power.

Referring to FIGS. 6A-6B, an empirical setup of the friction assisted tube forming for decreasing the diameter or radius of the tube 106 using a die 110 and a lathe machine 118 is disclosed. In one embodiment, the die 110 is securely and rotatably assembled to the spindle or chuck 114 of the lathe machine 118. The die 110 is configured to rotate by the machine head. In one embodiment, the tube 106 is forced across the die 110 for decreasing the diameter or radius. The die 110 is configured to rotate over the deformation area 108 of the tube 106, thereby generating thermal energy for easily softening and forming the tube 108 with a desired diameter or radius using a nominal pressing force without any additional equipment and power.

Referring to FIGS. 7A-7B, the empirical setup of friction assisted tube extrusion for decreasing the thickness of the tube 106 using the die 110, the inner mandrel 112, and the lathe machine 118 is disclosed. In one embodiment, the inner mandrel 112 and the tube 106 are assembled between the chuck/spindle 116 and the tailstock 114 of the lathe machine 118 simultaneously. In one embodiment, the die 110 is configured to rotatably secure to the spindle 116 of the lathe machine 118. In one embodiment, the tube 106 is forced across the die 110 for decreasing the thickness. The die 110 is configured to rotate over the deformation area 108 of the tube 106, thereby generating thermal energy for easily softening and forming the tube 108 with a desired thickness using a nominal pressing force without any additional equipment and power. In one embodiment, the friction assisted tube straining could be executed when the friction assisted tube forming for increasing and decreasing the diameter are sequentially repeated.

The advantages of the present invention include: the friction assisted tube fabrication includes a set of processes or methods such as a method for friction assisted tube forming, a method for friction assisted tube extrusion/extruding, and a method for friction assisted tube straining. The friction assisted tube fabrication forms metal objects, such as elongated members or tubes to a desirable diameter and a thickness with controllable mechanical properties. The friction assisted tube fabrication is inexpensive, simple, easy to operate, cost-effective, and safe for the operators. In one embodiment, the friction assisted tube fabrication enables the operator to simply fabricate complex structures and metal objects, such as elongated members or long tubes with less pressing force without any additional equipment and power.

The foregoing description comprise illustrative embodiments of the present invention. Having thus described exemplary embodiments of the present invention, it should be noted by those skilled in the art that the within disclosures are exemplary only, and that various other alternatives, adaptations, and modifications may be made within the scope of the present invention. Merely listing or numbering the steps of a method in a certain order does not constitute any limitation on the order of the steps of that method. Many modifications and other embodiments of the invention will come to mind to one skilled in the art to which this invention pertains having the benefit of the teachings presented in the foregoing descriptions.

Although specific terms may be employed herein, they are used only in generic and descriptive sense and not for purposes of limitation. Accordingly, the present invention is not limited to the specific embodiments illustrated herein. While the above is a complete description of the preferred embodiments of the invention, various alternatives, modifications, and equivalents may be used. Therefore, the above description and the examples should not be taken as limiting the scope of the invention, which is defined by the appended claims. 

1. A method for friction assisted forming a metal object into a tube, comprising: forcing the metal object with an initial radius across the slope of a mandrel with an angle; rotating the mandrel while forcing the metal object to deform into a tube with a desired radius, wherein the tube is in contact with the slope of the mandrel while rotating, thereby generating thermal energy to heat a deformation area of the tube for simply and easily softening and forming into a desired shape with a desired value of radius and dimensions using a nominal pressing force.
 2. The method of claim 1, wherein the metal object is a deformable tube.
 3. The method of claim 1, wherein the mandrel is configured to simply increase the radius of the tube by heating and softening the deformation area using thermal energy generated by friction between the tube and the slope of the mandrel while rotating.
 4. The method of claim 1, wherein the radius of the tube is decreased using a die.
 5. The method of claim 4, wherein the die is configured to slidably and rotatably secure to an external surface of the tube.
 6. The method of claim 4, wherein the die is further configured to rotate in a clockwise direction or a counterclockwise direction or with rotational oscillations.
 7. The method of claim 4, wherein the die is further configured to enable an operator to rapidly rotate over the deformation area of the external surface of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area for simply and easily softening and precisely decreasing the tube radius to a desired value using a nominal pressing force.
 8. A method for friction assisted extruding a tube, comprising: forcing the tube with an initial thickness across the slope of an inner mandrel; securing a die over an external surface of the tube and rapidly rotating the die over a deformation area of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area of the tube for simply and easily softening and precisely decreasing the tube thickness to a desired value using a nominal pressing force.
 9. The method of claim 8, wherein the inner mandrel is configured to securely hold the tube during the friction assist extruding process.
 10. The method of claim 8, wherein the die is configured to slidably and rotatably secure to an external surface of the tube.
 11. The method of claim 8, wherein the die is further configured to rotate in a clockwise direction or a counterclockwise direction or with rotational oscillations.
 12. The method of claim 8, wherein the die is further configured to enable an operator to rapidly rotate over the deformation area of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area of the tube for simply and easily softening and precisely decreasing the tube thickness to a desired value using a nominal pressing force.
 13. A method for friction assist tube straining to fabricate a metal object into a tube, comprising: forcing the metal object with an initial radius across a slope of a mandrel with an angle; rotating the mandrel while forcing the deformable tube to deform the metal object into a tube with a desired radius, wherein the tube is in contact with the slope of the mandrel while rotating, thereby generating thermal energy due to friction between the tube and the slope of the mandrel to heat a deformation area of the tube for simply and easily softening and forming into a desired shape with an accuracy radius and dimensions using a nominal pressing force, and securing a die over an external surface of the tube and rapidly rotating the die over a deformation area of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area of the tube for simply and easily softening and precisely decreasing the radius of the tube to a desired value using a nominal pressing force.
 14. The method of claim 13, wherein the metal object is a deformable tube.
 15. The method of claim 13, wherein the mandrel is configured to simply increase the radius of the tube by heating and softening the deformation area using thermal energy.
 16. The method of claim 15, wherein the thermal energy is generated due to friction between the mandrel and the external surface of the tube while rotating.
 17. The method of claim 13, wherein the die is configured to slidably and rotatably secure over the external surface of the tube.
 18. The method of claim 13, wherein the die is further configured to enable an operator to rapidly rotate over the deformation area of the external surface of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area for simply and easily softening and precisely decreasing the tube radius to a desired value using a nominal pressing force.
 19. The method of claim 13, wherein the inner mandrel is configured to securely hold the tube.
 20. The method of claim 13, wherein the die is further configured to enable an operator to rapidly rotate over the deformation area of the tube, thereby generating thermal energy due to friction between the external surface and the die to heat the deformation area of the tube for simply and easily softening and precisely decreasing the tube thickness to a desired value using a nominal pressing force. 